Machine for cutting curved surfaces



2 SheetsSheet l.

(No Model.)

S. M. DIXON. MACHINE FOR CUTTING OURVED SURFACES.

Patented Aug 13, 1889.

(No Model.) v 2 Sheets-Sheet 2.

S M. DIXON. I MACHINE FOR CUTTING GURVED SURFACES.

No. 409,024. Patented Aug. 13, 1889.

uEWa rweys.

m; PETERS, Pheto-Lilhogn han Wasnmgmji a UNITED STATES PATENT OFFICE.

SAMUEL lWI. DIXON, OF MILIVAUKEE, IVISOONSIN.

MACHINE FOR CUTTING CURVED SURFACES.

, SPECIFICATION forming part of Letters Patent No. 409,024, dated August 13, 1889. Application filed October 23, 1888. Serial No. 288,949. (No model.)

clare that the following is afull, clear, and eX.

. act description of the invention, which will enable others skilled in the art to which it perrains to make and use the same, reference being had to the accompanying drawings, and to the letters of reference marked thereon, which form a part of this specification.

The object of myinvention is to produce a cut on a varying, irregular, or compound curve.

It consists, essentially, of a cutter susceptible of a variable curvature, together with mechanism for supporting, changing the curvature of, and guiding the cutter, suitable feeding and driving mechanism, means for supporting and holding the work in proper position, 850.

My invention is applicable to the manu factu re from any suitable material of all manner of articles having curved faces-such as staves, chair backs and bottoms, carriagepanels, &c.-but for the purpose of illustra tion I have shown a machine designed particularly for sawing staves and like articles.

Referring to the accompanying drawings, in which like letters designate the same parts in the several figures, Figure 1 is a perspective View of a stave-sawin g machine embodying my invention. Fig. 2 is a vertical longitudinal section of the same on the line cc :0, Fig. 3. Fig. 3 is an elevation of the righthand end of the machine as-viewed in Figs. 1 and 2. Fig. 4 is a cross-section on the line 3 y, Fig. 2, showing on an enlarged scale the vibrating saw-frame, curved saw-guides, and the shaft on which they are supported. Fig. 5 is a cross-section on the line z .2, Fig. 4, of one of the arms of the saw-frame, showing in plan view one of the saw-holding blocks; and Fig. (3 is a side elevation, on an enlarged scale,

of one of said blocks.

able frame-work. Upon this shaft is mounted the vibrating cross-head B, to the ends of which are adj ustably secured, at the desired inclination thereto, the depending slotted arms I) b, constituting, in connection with said cross-head, the saw-frame. On opposite sides of said saw-frame are loosely mounted on said shaft A vibratory inverted-U-shaped crossheads D D, to the depending ends of which are attached the removable guides or patterns D D, parallel with the shaft A, so as to pass lengthwise freely through the slots of arms Z) Z). The patterns D D are formed to the desired curve on their upper edges, which gave on each side laterally-projecting flanges c d.

C O are saw-holding blocks reduced to cylindrical form to fit between the four sections of arms I) b, as shown in Figs. 4, 5, and 6, and to turn freely in boxes 0 c, which areplaced over the cylindrical reductions of said blocks and are fitted between opposite sections of said arms I) b, as shown in Fig. 5. These boxes 0 c are divided axially and vertically to permit of their being placed in the grooves in said blocks G C, around the reduced cylindrical parts thereof, and are constructed to move freely up and down between the arms Z) l), by which they are held in place.

The blocks C O are formed near their inner ends with transverse cylindrical holes, open at the sides through the ends of said blocks, as shown in Figs. etand 6. They are also formed, between the grooves therein, with transverse T-shaped openings, through which the flanged upper edges of the patterns D D pass. The saw E is preferably serrated on both edges, so as to cut in both directions. It is secured at the ends in the sides of cylinders e e, which are fitted to and inserted in the transverse holes in said blocks 0 O, the saw passing through the slotted openings in the ends of the blocks, as clearly shown in Fig. 4.. The cylinders ee are retained in said blocks by screws and washers e e, which overlap their ends, or by any other suitable means. They turn freely in the blocks 0 O and permit of variation in the curvature of saw E as the blocks approach or recede in moving up and down in the arms I) b.

The saw-frame is prevented from moving lengthwise on the shaft A by a fixed sleeve to on the standard A, in which the hub of the cross-head B is retained by a nut 12 or other suitable means, while the cross-heads D D,

carrying the patterns D I), are free to move lengthwise of said shaft and partake of the vibratory movement of the saw-frame.

F is the driving-shaft supported in boxes a a on standards A A, or other suitable supports, parallel with. the shaft A. Upon this shaft are mounted the crank-wheel f, eccentric f tight and loose pulleys f f and balance-wheel f. The crank-wheel f is connected by the pitman f with an arm 1), projecting upwardly from the cross-head B. The pulleys f f are connected with any suitable source of power, and the eccentric f is connected with the carriage-feedin g mechanism hereinafter described.

G is a carriage supported and adapted to be moved on suitable ways 9 g, parallel with the shaft A. To diagonally-opposite corners of said carriage are attached standards 9 9', formed at their upper ends with sleeves for the reception of the hubs of cross-heads D D, which are retained therein by nuts 1 g as shown in Fig. 2. By this means the patterns D I) are caused to move with the carriage G.

H is a vertically-movable work-support provided with four cog-toothed legs or racks, which pass through mortises in the carriage G and engage with gears I I, by means of which said work-support II is raised and lowered. These gears I I work togethcror intermesh in pairs on each side of the carriage, and the shafts on which they are mounted have bearings in and are movable with carriage G, as shown in Figs. 1, 2 and 3. One of the shafts of the gears I is provided with a crank I, by means of which the work-support II is manually operated, and with a ratchet-wheel I engaged by a pawl 1', pi voted to the carriage for preventing the descent of said work-support as it is raised. Any suitable mechanism, which will readily suggest; itself, may be employed instead of the crank for automatically lifting the work-support If an interval at each reversal of the movement of carriage G.

The work-support II is longitudinally slotted and provided with dogs h it, one at each end, guided and adapted to move in the slots therein, as shown in Figs. 1 and 2. A screwshaft 71 provided at one end with a crank 71? for turning it, and journaled in the ends of said work-support ll, underneath and parallel with the slots therein,is formed with right and left screw-threads, one of which works with a corresponding nut in one dog h,while the other works with a similar nut in the other dog. By turning the screw-shaft- 71 in one direction the dogs 71 71 are caused to simultaueously approach each other toward the center of the work-support II. Turning the screw-shaft in the reverse direction causes said dogs to recede in like manner toward the ends of said work support. By this means the block to be sawed or cut is always dogged in the center of the work-support and travel of the carriage.

Underneath the carriage G are journaled,

in suitable supports at or near the ends of said carriage, when the same is in its middle position, four chain-wheels K K, two side by side at each end. Upon these wheels are mounted two parallel endless chains 7a, to which are secured the ends of a cylindrical crossshaft 76', as shown in Fig. 2. Upon the shaft 70, between said chains, is mounted so as to turn freely thereon a perforated block g", held and adapted to move freely up and down in a vertical slot in the upright arm attached to the under side of the carriage G. Each chain-wheel K is mounted upon an independent shaft, so as to leave a clear space between them for the passage of the arm 4*, as shown in Fig. 3.

At one end of the machine is supported in suitable bearings a cross'shaft Z, upon which are mounted two ratchet-wheels L L and two gear-wheels Z l, as shown in Figs. 1, 2, and 3. The gears Z Z engage with and drive the gears k one mounted on each of the shafts of the adjacent pair of chain-wheels K K.

N is a U-shaped pawl-carrier, hinged at its ends on the shaft Z justoutside of the ratchetwheels L L. To the pawl-carrier N are pivoted pawls an, adjacent to the ratchet-wheels L L, with which they are held in engagement by the springs n n, said springs allowing the pawls to slide over the teeth of the ratchetwheels when the pawl-carrier descends. The pawl-carrier N is connected with and operated by the eccentric f through the strap m and connecting-rod 'm, whereby the feed of the carriage G is made to correspond and vary with the movement of the saw E, which is driven from the same shaft. The feed of said carriage is varied as desired by setting the adjustable hub of the eccentric f nearer to or farther from the center.

I do not wish to be undeisi'ocd as restricting myself to the precise construction and arrangement of mechanism hcreinbefore described, inasmuch as it is susceptible of various changes and modifications within the spirit and intent. of my invention.

My improved machine operates as follows: Taking, for example, the machine shown in the drawings, which is arranged to saw staves and the like, patterns I) D, of the required curvature, are employed to give the required longitudinal curvature to the stave. The arms I) I) are also set at the required inclination to the cross-head B to produce, in eo-operation with said patterns by gradual changes in the curvature of the saw, a cut of gradually-iucreasin g curvature from the center toward the ends of the stave to correspond with the distance from the axis of the barrel, &c., to any point in the length of the stave. The block to be sawed or cut is secured in place and centered on the support II by the dogs h it, operated by means of the screwshal't 71 and crank h It is then raised to the required height bymeans of the crank I, and held at that elevation by the ratchet wheel I and pawl i. The driving-shaft F is and slotted arm 9 move the carriage G and support II intermittingly in one direction on' the ways 9 g, till the shaft 7t, carrying the block 9 passes around the chain-wheels at one end of the machine, when the movement of said carriage is retarded and momentarily arrested. Returning on the opposite side of the chain-wheels, the block g moves the car riage in like manner in the reverse direction. The saw-frame engaging by its arms I) b the patterns D D causes them and the crossheads D D, to which they are attached, to vibrate therewith on the shaft A. At the same time said cross-heads and patterns are moved with the carriage lengthwise of said shaft by means of the standards g g. As the sawholding blocks O O are moved upwardly in the slotted arms Z) Z) by the longitudinal movement of the patterns D D, they approach each other and the curvature of the saw E is consequently increasechand vice versa. The curved flanged patterns D D, engaging the T-grooves in the blocks 0 C, turn the same as they pass through them and maintain the blade of the saw at an inclination crosswise corresponding to the inclination of that portion of the curved faces of said patterns in contact with said blocks 0 0, thus causing the saw to produce a cut varying in curvature in the direction of the saw-stroke and corresponding in curvature in the direction of the feed to the curvature of the patterns. The saw having teeth on both edges, the block is raised an interval, as described, at each reversal of the movement of the carriage, and a stave of section is cut by the movement of the carriage in each direction.

It is obvious that a great variety of curved surfaces suitable for various articles may be produced by changing the contour of the pat terns D D, which may be formed on anydesired curve or combination of curves.

The arms I) 1) should be set at the required angle to hold the cutting-edges of the saw as it approaches or recedes from the axis of oscillation in arcs of concentric circles, the centers of which are in said axis of oscillation of the saw-frame. hen the ends of the saw are brought nearer to each other to produce a kerf of smaller radius, itis obvious that the middle of the blade will belowered relatively to its ends, and for this reason the longitudinal curve of the cut will not be as sharp toward the ends as the curvature of the guides. Consequently, to producea cut of agivenlongitudinal curvature, the guides must be formed on a gradually-increasing curvature toward the ends. The saw is caused to bend in its various positions to the required arcs by making it a little more flexible at the ends and allowing it to turn freely at the ends on the cylindrical bearings e e. \Vhen the saw is turned by the guides to cut upward or clownward, the upper edge, being nearer the axis of oscillation, will be bent to the arc of a smaller circle; but as each longitudinal section of the saw'blade arrives at any point in the cut it will assume the curve to which the cutting-edge was bent at that point. If the cutting-edges of the saw are maintained in arcs of concentric circles, its ends will describe in their movement toward and from the axis of oscillation lines curved slightlyoutward at the middle; but the deviation from straight .lines is so slight that in practice it may be generally, if not always, disregarded and the arms 17 I) made straight.

I clain1 1. In a machine for producing a cut of variable curvature, the combination of a flexible saw or cutter and means of changing its curvature while it is making a cut, substantially as and for the purposes set forth.

2. In a machine for producing a cut of variable curvature, the combination of a flexible cutter, holders supporting the cutter on opposite sides of the work, and mechanism connected with and arranged to change the distance between said holders while the cutter is in operation, substantially as and for the purposes set forth.

3. In a machine for producing a cut of variable curvature, a flexible cutter, means for changing its curvature while in operation, and a pattern arranged to change the direction of the cut transversely to the direction of the stroke of the cutter, substantially as and for the purposes set forth.

4. In a machine for producing cuts of variable curvature, a flexible cutter, means for changing the curvature of said cutter when the same is in operation, feeding mechanism, and mechanism for changing the position and inclination of the cutter with reference to the line of feed, substantially as and for the purposes set forth.

5. In a machine for producing a cut of irregular or variable curvature, the combination of a flexible cut-ter, feeding mechanism, saw-holding devices and guides arranged to change the curvature of the cutter, and apattern arranged to change the position of the saw, whereby its curvature is changed and at the same time the line of its out in the direction of the feed is determined, substantially as and for the purposes set forth.

6. In a machine for producing a cut of irregular or variable curvature, the combination, with a vibratory saw-frame provided with inclined guide-arms, saw-holding blocks held to said arms, a flexible saw secured to said blocks, and mechanism arranged to move said blocks lengthwise of said arms, whereby IIO the curvature of the saw is changed, substantially as and for the nirposes set forth.

7. In a machine for producing a cut of irregular or variable curvature, the combination of a viln'atory saw-frame, a flexible saw held in said frame, and a pattern arranged to move said saw while the same is in operation toward or from the center on which said frame vibrates, substantially as and for the purposes set forth.

8. In a machine for producing a cut of irregular or variable curvature, the combination of a vibratory saw-frame having slotted arms, saw-holding blocks held and capable of turning in said arms, a saw secured to said blocks, and curved patterns engagingwi th said blocks and arranged to move and turn the same in said arms in conformity with the curvature of the cut to be produced, substantially as and for the purposes set forth.

9. In a machine for producing a cut of i1- regular or variable curvature, the combination, with a vibratorysaw-frame having movable saw-holding blocks, of means formoving said blocks toward or away from each other, and a flexible saw secured at the ends in cylinders which. have bearings and are capable of turning in said blocks, substantially as and for the purposes set forth.

10. In a machine for producing a cutot' irregular or variable curvature, the combination of: a vibrating saw-frame having inclined slotted arms, saw-holding blocks journaled in and movable lengthwise of said arms, a flexible saw secured at the ends in cylinders which are held and are capable of turning in transverse holes in said blocks, and curved patterns working longitudinally through transverse openings in said blocks, substantially as and for the purposes set forth.

II. In a machine for producing a cut of ir regular or variable curvature, a fixed shaft, a vibrating saw-frame mounted thereon and having inclined arms, saw-holding blocks carried by and movable lengthwise of said arms, a flexible saw secured at the ends to said blocks, vibrating cross-heads mounted on said shaft on opposite sides of said saw-frame, patterns attached to said cross-heads and movable lengthwise in engagement with said blocks, and a carriage movable parallel with said shaft and connected with said crossheads, substantially as and for the purposes set forth.

1?. In. a machine for producing a cut of irregular or variable curvature, the combination of: a flexible saw or cutter, means for changing the curvature of said saw while the same is in operation, a carriage nuivable on suitable ways, chain-wheels carrying parallel chains, and a cross-shaft attaehtal to said chains and connected with and movable l( ngthwise of an arm attached to said carriage perpendicular to its line of travel, substantiall y as and for the purposes set forth.

1-). In a machine for producing a cut of irregular or variable curvature, the combination of a vibrating sa-w-fran'le having inclined arms, a flexible saw having sliding connections with said arms, a carriage capable of rectilinear movement transversely to the stroke of said saw, mechanism for feeding said carriage and curved patterns connected with said carriage and saw-frame so as to partake of the movements of each, and also connected with the ends of the saw so as to move the same lengthwise of the inclined arms of the saw-frame, and thereby produce a greater or less curvature of the saw, substantially as and for the purposes set forth.

It. In a machine for producing a cut of irregular or variable curvature, a vibrating saw adj ustably held therein, guides arrai'iged to change the curvature of the saw while the same is in operation, a work-support, feeding mechanism for moving said support transverscl y to the stroke of the saw, and mechanism for moving said support transversely to the feed toward and from the plane of the saw, substantially as and for the purposes set forth.

15. In a machine for producing a cut of irregular or variable curvature, the combination of a vibrating saw-frame having inclined arms, a flexible saw held at the ends in blocks so as to turn therein on axes transverse to its blade, said blocks being attached to and movable lengthwise of said inclined arms and. capable of turning, a carriage movable transvcrsely to the saw, and curved patterns connected and movable with said carriage and saw-frame and provided with flanged edges which engage with undercut grooves in said saw-holding blocks, substantially as and for the purposes set forth.

16. In a machine for producing a cut of irregular or variable curvature, the combination of a flexible saw or cutter, a work-support, mechanism for moving the same past the saw, a pattern which determines the dircction of the cut in the line of the feed, and mechanism arranged to increase or diminish the curvature of the saw in the direction of its stroke, according to the curvature of the cut in the line of feed, substantially as and for the purposes set forth.

In testimony that. I claim the foregoing as my own I affix my signature in presence of two witnesses.

SAML. M. DIXON.

\Vitnesses:

(f rms. Ti. (loss, i if. 'BorrUn. 

